Table 2.
The IDO-1 inhibitory activity of o-naphthaquinone derivatives in enzyme- and cell-based assays.
| Compound Number | R1 | R2 | Enzymatic IC50 (μM) or Inhibitory Rate at 20 µM a | Cellular IC50 (μM) a | |
|---|---|---|---|---|---|
|
6 | H | H | 23.1 ± 1.6% | — b |
| 7a |
|
H | 3.72 ± 0.45 | — | |
| 7b |
|
H | 4.72 ± 0.30 | — | |
| 7c |
|
|
29.3 ± 2.2% | — | |
| 7d |
|
|
21.5 ± 1.1% | — | |
| 7e |
|
H | 7.47 ± 3.58 | — | |
| 7f |
|
H | 2.74 ± 0.10 | — | |
| 7g |
|
H | 7.05 ± 2.46 | — | |
| 7h |
|
H | 48.0 ± 3.2% | — | |
| 7i |
|
H | 54.5 ± 2.3% | — | |
| 7j |
|
H | 60.4 ± 3.9% | — | |
| 7k |
|
H | 4.60 ± 2.81 | — | |
| 7l |
|
H | 5.71 ± 0.47 | — | |
| 7m |
|
H | 4.96 ± 2.02 | — | |
| 8 | OH | H | 2.83 ± 0.12 | — | |
|
9 | H | 61.2 ± 2.1% | >10 | |
| 10 | OH | 3.10 ± 1.02 | >10 | ||
|
11 | H | 0.84 ± 0.26 | >10 | |
| 12 | OH | 0.37 ± 0.02 | 3.85 ± 0.86 | ||
|
14 | H | 52.7 ± 2.5% | >10 | |
| 15 | OH | 68.0 ± 8.6% | — | ||
| Epacadostat | 0.086 ± 0.009 | 0.023 ± 0.003 | |||
a The values are the mean ± SE of two independent experiments; b Not determined.